1. Field of the Invention
The invention disclosed and claimed herein generally pertains to an apparatus and method for determining the orientation of a blade server, or other member used to support electronic components, when the blade server or other member is inserted into a blade chassis or enclosure. More particularly, the invention pertains to apparatus of the above type wherein the blade server or other member is adapted for insertion into either vertical or horizontal slots formed in the chassis, and blade orientation must be determined in order to properly orient an information display on the front panel of the blade server. Even more particularly, the invention pertains to apparatus of the above type which is comparatively simple and avoids the need for an orientation sensor or the like, while maintaining the front panel display in an upright position, for any blade orientation.
2. Description of the Related Art
As is known by those of skill in the art, blade servers, also referred to herein as blades for convenience, are self-contained computer servers designed for high density. Multiple blades can be readily inserted into an enclosure such as a chassis or the like, by means of slots formed therein, in order to provide various useful products. For example, a product of IBM known as the 8677 IBM BladeCenter® chassis has slots to receive up to 14 blade servers, and can be used in connection with small computer system interface (SCSI) storage expansion units or the like. Moreover, some blade servers provide a display on the front panel or face thereof, that is, on the blade edge that remains viewable when the blade has been inserted into a blade chassis. This display can provide a user with important information regarding operation of the blade server, and may comprise an array of light-emitting diodes (LED's), or may comprise various other graphic elements.
At present, blade server chassis typically provide slots that are oriented either vertically or horizontally, that is, oriented along either vertical or horizontal axes. In view of this, certain manufacturers have sought to provide blade servers that can be interchangeably used in chassis that have either vertical or horizontal slots. This, of course, is intended to enhance versatility in the use of blade servers. Moreover, when a blade server is inserted into a chassis, a set of connectors on the blade engage and mate with complementary connecting structure in the blade chassis, in order to exchange network and other signals, and also to supply power to the blade. Efforts have been made to configure blade servers so that they can be inserted into slots in either of two orientation modes, where the blade server is rotated by 180° between the two modes. To support this effort, the blade server is provided with two sets of connectors, where the two sets are mirrored to one another. That is, for each orientation mode of the blade when inserted into a slot, at least one of the blade connector sets will mate with the blade chassis connectors.
It will be seen that the above enhancements to blade servers, taken together, require a blade to be usable in any of four orientations, that is, two vertical and two horizontal orientations. Notwithstanding the benefit of these enhancements, it will be recognized that the display on the front panel of the blade server must be somehow adjusted, as the blade is used in different orientation modes. Otherwise, a user could be required to view information provided by the display panel in an upside down position, or at 90° to a vertical position. This could be very inconvenient, and could result in information being overlooked or misread. Moreover, as blade server front panel displays become further developed, using graphic technologies such as liquid crystal devices (LCD's) and organic LED's (OLED's), it will become increasingly important for information provided by the displays to appear upright, regardless of blade orientation, so that such information can always be easily and accurately read and comprehended.
Currently, techniques are available for constructing a front panel blade server display that can be adjustably rotated or reoriented, so that features of the display, such as alphanumeric characters or colored icons, will always appear in an upright position. However, in order to make adjustments using these techniques, it is still necessary to determine the particular orientation of the blade server, after the blade has been inserted into a chassis. In one approach for determining the orientation of an object, an electronic tilt sensor makes use of a ball bearing and several electronic contacts. This approach, however, as well as other solutions that use a sensor device of some type, tend to require space that is not practically available in the environment in which blade servers are used. Also, such solutions can entail excessive cost. Accordingly, it would be very desirable to provide a comparatively simple and inexpensive means for detecting the orientation of a blade server, upon inserting the blade into a blade chassis, that does not need a sensor mechanism nor any other significant parts or components.